This disclosure generally relates to tools used in oil and gas wellbores. More specifically, the disclosure relates to drillable packers and pressure isolation tools.
In the drilling or reworking of oil wells, a great variety of downhole tools are used. Such downhole tools often have drillable components made from metallic or non-metallic materials such as soft steel, cast iron or engineering grade plastics and composite materials. For example, but not by way of limitation, it is often desirable to seal tubing or other pipe in the well when it is desired to pump a slurry down the tubing and force the slurry out into the formation. The slurry may include for example fracturing fluid. It is necessary to seal the tubing with respect to the well casing and to prevent the fluid pressure of the slurry from lifting the tubing out of the well and likewise to force the slurry into the formation if that is the desired result. Downhole tools referred to as packers, frac plugs and bridge plugs are designed for these general purposes and are well known in the art of producing oil and gas.
Bridge plugs isolate the portion of the well below the bridge plug from the portion of the well thereabove. Thus, there is no communication from the portions above and below the bridge plug. Frac plugs, on the other hand, allow fluid flow in one direction but prevent flow in the other. For example, frac plugs set in a well may allow fluid from below the frac plug to pass upwardly therethrough but when the slurry is pumped into the well, the frac plug will not allow flow therethrough so that any fluid being pumped down the well may be forced into a formation above the frac plug. Generally, the tool is assembled as a frac plug or bridge plug. An easily disassemblable tool that can be configured as a frac plug or a bridge plug provides advantages over prior art tools. While there are some tools that are convertible, there is a continuing need for tools that may be converted between frac plugs and bridge plugs more easily and efficiently. In addition, tools that allow for high run-in speeds are desired.
Thus, while there are a number of pressure isolation tools on the market, there is a continuing need for improved pressure isolation tools including frac plugs and bridge plugs.